Interrupter for ignition-dynamos.



C. T. MASON. INTERRUPTER FOR lGNITION DYNAMOS.

APPLICATION FILED APR. 29. I918.

Patented Jan. 7', 1919.

3 SHEETS-SHEET I.

aw/ Mano C. T. MASON. INTERRUPTER FOR IGNITION DYNAMOS. APPLICATIONFILED "3.29.1918.

Patnted Jan; 7,1919.

1,290,624. I 3 SHEETS-SHEET 2.

C. T. MASON. INTERRUPTER FOR IGNITION DYNAMOS.

APPLICATION HLE D APR. 29. I918. 1,290,624. Patented Jan. 7,1919. I{SHEETS-SHEET 3.

' v v 6140mm UNITED'STATES PATENT OFFICE.

CHARLES THOMAS MASON, 0F SUMTEB, SOUTH CAROLINA, ASSIGNOR TO SPLITDORFELECTRICAL COMPANY, OF NEWARK,

JERSEY.

Specification of Letters Patent.

NEW JERSEY, A CORPORATION OF NEW INTERBUPTER FOR IGNITION-DYNAMICS.

Patented Jan. 7, 1919.

Application filed April 29, 1918. Serial No. 231,481.

To all whom it may concern:

Be it known that I, CHARLES THOMAS SON, a citizen of the United States,residing at Sumter, in the county of Sumter and State of South Carolina,have invented cer- .tain new and useful Improvements in Interrupters forIgnition-Dynamos, of which the followin is a specification, referencebeing had to t e accompanying .and wherein the resistance of saidcontacts when closed is reduced by other contacts of relatively highconductivity arranged 11f multi le with the first named contacts forbreaking the circuit and which are timed So as to open before and closeafter the contacts which interrupt or break the primary circuit. Thepresent invention is directed to an improvement in the interrupter of myprior application for accomplishing the purpose set forth therein.

An object of the invention is to provide an interrupter having aplurality of pairs of contacts timed so that one pair open before andclose after the other pair wherein the pairs of contacts are arrangedconcentric to each other so as to reduce to a minimum the space in whichthe contacts are located and so as to simplify the construction of theinterrupter.

A further object of the invention is to rovide an interrupter mechanismof the a ve character .wherein the inner pair of contacts are formed ofmetal of relatively low conductivity, while the outer pair of contactsare formed of metal of relatively high conductivity.

- Still another object of the invention is to provide an interrupter ofthe above char acter wherein the inner stationary contact is adjustablymounted in the outer stationary contact and wherein the outer stationarycon- .tact may be adjusted for varying the position of both stationarycontacts.

These and other objects will in part be obvious and will in part behereinafter more fully disclosed.

In the drawings .which show b way of illustration one embodiment of t einvention;

Figure 1 is an end view of a magneto generator having my improvedinterrupter applied thereto, the end cap being removed to show theinterrupter mechanism; 7

Fig. 2 is a side view of the magneto generator and a vertical sectionalview on the line'2-2 of Fig. 1;

Fig. 3 is a view showing more or less diagrammatically the interruptermechanism, both pairs of contacts being closed;

Fig. 4 is a similar view but showing the outer pair of contacts asseamed;

Fig. 5 is a similar view ut showing the operating cam turned so as toseparate both pairs of contacts; and

Fig. 6 is a detail inplan showing a por-' tion ofthe supporting bracketand the stationary contacts.

Theinvention is embodied broadly in an "interrupter for breaking thecircuit of a high tension ignition system, which interrupter includestwo pair of contacts, one of which is of higher conductivity than theother, as for example, one pair of contacts may be made of silver whilethe other pair is made of tungsten. One contact in each pa1r 1s fixed,while the other contacts are carried by a movable lever which isoperated by a camon the main shaft of the magneto generator. The pairsof contacts are arranged concentric to each other. The inner stationarycontact is carried by a part which is threaded into the part whichcarries the outer stationary contact. The outer stationary contact ispreferably ring shaped and the inner stationary contact is spacedtherefrom at the sparking surface. The part carrying the outerstationary contact is threaded into a bracket and is capable of endwiseadjustment therein "The movable contacts as above noted, are bothcarried by a single lever. The outer contact is rin shaped to correspondwith the ring shapes fixed contact with which it cooperates. This outerring shaped contact is directly fixed or arm which is fixed to thelever.

that as the lever moves toward the station-.

ary contacts the inner movable contact fi rst makes engagement with itscofiperating member, after which the arm carrying the same yields toallow the lever to continue its movement until the outer movable contactmakes engagement with the outer fixed contact.

Referring more in detail to the drawings, I have shown my improvedinterrupter as applied to a magneto generator indicated at 1. It will beunderstood of course that the interrupter may be used in otherconnections than with magneto generators. The interrupter includes apair of contacts indicated at 2 and 3 which are the main contacts'formaking and-breakin the circuit. These contacts are prefera ly made ofmetal of relatively low conductivity, such an tungsten. The interrupteralso includes secondary contacts, which may be said to be the auxiliarycontacts and they are indicated at \4 and 5 in the drawings. Theseauxiliary contacts are of metal of relatively high conductivity such assilver. The stationary contacts 3 and 4 are mounted in a bracket 6 whichis secured to the magneto by suitable screws 7 and 8. These screws areinsulated from the frame by suitable insulation indicated at 9 and thebracket is also insulated from the frame by suitable insulationindicated at 10. The outer stationary contact 4, which is preferably ofsilver. is ring shaped and this ring shaped contact may be welded orotherwise secured to a sleeve 11,'which is threaded into the outstandingend 12 of the bracket 6. This outstanding end of the bracket is split asindicated at 13 and a screw 14 passes through the split end andserves-as a means for clamping the sleeve 11 in various adjustedpositions. Threaded into'the sleeve 11 is a stem or rod 15. The fixedcontact 3 is welded or otherwise secured to this stem or rod 15'. Saidcontact; -.3 is of .slightl less diameter than the inner diameter o thesilver ring contact 4," so. that it is spaced therefrom. The stemor rod15 is threaded into the sleeve 11 and is held in a listed positionstherein by a lock nut 16. rom the above it will be apparent that yloosening the nut 16, the stem or rod 15 may be raised and lowered andthe fixed contact carried thereby, adjusted relative to the contact 4and also by loosening the screw 14 the sleeve 11 may be adjustedvertically, which bring about an adjustment of both of the fixedcontacts.

The contact 5 is in the form of a sleeve or ring having substantiallythe same inner.

diameter as the ring 4. This contact is carried by a lever 17 which ispreferably stamped out of sheet metal and bolted to a fulcrum block 18,which is pivoted to .swing about a pivot 19. Secured to the under faceof the lever 17 is a bumper block 20 which rides on a cam 21 secured tothe main shaft. This cam 21 has a cut away section 22. A spring 23 issecured to a bracket arm 24 at one end thereof and the other end of thisspring is secured by a screw 25 to the fulcrum block 18. This springnormally turns the lever in a clockwise direction about its pivotalsupport 19 and thus forces the bumper 20 into engagement with the rotating cam 21 and also forces the movable contacts into engagement with thefixed contacts when the cam 21 turns to a position to permit the lever17 to swing, to bring about the engagement of the contacts. The rim orsleeve shaped contact 5 is preferably formed with a reduced section 26which fits an opening in the lever 17 and the upper end of the ring orsleeve contact is spun over onto the upper face of the lever,thus-firmly securing the contact member 5 to the lever. The movablecontact 2 is in' the shape of a cylinder and is of less diameter thanthe inner diameter of the ring or sleeve contact 5, so that this innercontact 2 may freely move in the outer contact. The inner contact member2 is'carried by a spring arm 27 which is fixed to the lever 17 by ascrew 28. This screw also serves to secure the lever 17 to the fulcrumblock 18 for the lever 17.

From the above it will be apparent that when the parts are in theposition shown in Fig. 3 the cut away part 22 of the cam 21 is directlybeneath the bumper block 20 and the'spring 23 has forced both pairs ofcontacts into engagement. While in this position the circuit through theprimary coil of the magneto generator is completed through both pairs ofcontacts. One end of the primary coil of the magneto generator isindicated at 29, Figs. 1 and 2 of the drawings-and this terminal of theprimary coil is connected toa screw- 30 threaded into the bracket 6 andthe bracket 6 of course has metallic connection with both of the fixedcontacts of the circuit interrupter. When'the cam is rotated to theposition shown in Fig. 4 the lever 17 is raised so as to separate thecontacts 4 and 5. The spring arm 27 which supports the inner movablecontact holds the inner contacts in engagement and the lever 17 is nowmoied so as to engage the spring arm whereby any further movement of thelever will lift the spring arm 27 and raise the inner movable contact.In Fig. 5 of the drawings, I have shown both of the contacts separated.

From the above it will be apparent that in my improved interrupter thecircuit is broken by the separating of the inner pair of contacts whichare of relatively low conductivity. After these contacts are closed,then the outer pair of contacts come into engagement and as thesecontacts are of relatively high conductivity the resistance in theprimary circuit offered by the first pair of contacts of lowconductivity, is greatly reduced, thus permitting the primary circuit ofthe magneto generator to quickly build up to a maximum. These outercontacts of relatively high conductivity will be first opened so thatwhen the spark is produced it will occur at the main inner contactswhich are of metal of rela-' ltively low conductivity. This throwing ofthe spark due to the breaking of the circuit on the tungsten contacts,prolongs greatly the life of the interrupter over that type ofinterrupter where the contacts are of relatively high conductivity andthis further establishing of the circuit by contacts of relatively highconductivity in multiple with the-contacts of low conductivity aftersaid contacts. of low conductivity are (closed, greatly reduces theresistance incident thereto and enables the generator to pick up morequickly and efliciently so as to produce a spark. By the arrangement ofthe contacts as above described, I have been able to form an interruptermechanism which is very simple in construction and of few parts. Whereone contact is within the other, the width of the interrupter ispractically no greater than in the case where a single pair of contactsis used, so that the interrupter mechanism may be placed in acomparatively small lace and as a matter of fact substituted or otherintcrrupters having the single pair-of contacts without requiring areorganization of the "mechanism thereof.

It is obvious that minor changes in the details of the construction maybe made without departing from the spirit of the in vention as set forthin the appended claims.

Having thus described the invention what is claimed as new is 1. Aninterrupter mechanism for ignition systems comprising a pair of maincontacts, one of which is movable 'for breaking a circuit for producingan ignition spark, a pair of auxiliary contacts in multiple with saidmain contacts and one of which is movable, said auxiliary contacts beingtimed so as to open before and close after said main contacts, saidpairs of contacts being so constructed and arranged that one pair isconcentric to the other. v

2. An interrupter mechanism for ignition systems comprising a pair ofmain contacts,

of auxiliary contacts in multiple with said main contacts and one ofwhich is movable, said auxiliary contacts being timed so as to I openbefore and close after said main contacts, said auxiliary contacts beingring shaped and surrounding said main contacts.

3. An interrupter mechanism for ignition systems comprising a pair ofmain contacts, one of which is movable for breaking a circuit forproducing an ignition spark, a pair of auxillary contacts in multiplewith said main contacts and one of which is movable, said auxiliarycontacts being timed so as to open before and close after said maincontacts, one of said stationary contacts being 80 carried by andlocated within the other stationary contact.

4;. An interrupter mechanism for ignition systems comprislng a pair ofmain contacts, one of which is movable for breaking a circuit forproducing an ignition spark, a pair of auxiliary contacts in multiplewith said main contacts and one of which is movable,

said auxiliary contacts being timed so as to open before and close aftersaid maincon tacts, one of said stationary contacts being carried by andlocated within the other stationary contact and means whereby saidstationary contacts may be simultaneously adjusted and whereby the innercontact may be adjusted in the outer contact.

5. An interrupter mechanism for ignition systems comprising a .pair ofmain contacts, one of which is movable for breaking a circuit forproducing an ignition spark, a pair of auxiliary contacts in multiplewith said main contacts and one of whichis movable, said auxiliarycontacts being timed so as to open beforeand close after said maincontacts, said main contacts being disposed within said auxiliarycontacts, said auxiliary contacts being ring shaped and spaced-from themain contacts.

6. An interrupter mechanism for ignition systems comprising a pair ofstationary con- 110 tacts, a bracket supporting said stationarycontacts, a pair of movable contacts cooperating respectively with thestationary contacts, a lever supporting said movable con-t tacts and oneof said movable contacts being 1 ring shaped and fixed to said lever,the other of said movable contacts being shaped so as to extend throughthe ring shaped contact and spaced therefrom and a spring arm carried bvsaid lever and carrying the inner 120 movable contact, said contactsbeing so disposed that'the inner movable contact makes engagement withits cooperating contact prior to the engagement of the outer movablecontact with its coiiperating contact.

7. An interrupter mechanism for ignition systems comprising a supportingbracket, a sleeve adjustably-mounted in said bracket and carrying a ringshaped auxiliary contact at its upper end, a stem threaded 1nto 0 saidcontacts, a spring for moving the lever .toward the contacts, anauxiliary ring shaped contact carried by the lever and co- 0 cratingwith the ring shaped contact on t e sleeve, a spring arm carried by thelever,

a cylindrical contact carried by said spring arm and extending throughthe ring contact on the lever and adapted to engage the contact on theadjustable stem, said inner movable contact on the lever being disposedrelative to the stationary contacts whereby the ring shaped contactswill be first separated when the lever is moved by the cam, after whichthe inner pair of contacts are separated for breaking the circuit andwhereby said inner pair of contacts will first come into engagement forcompleting the circuit, after which the outer rin shaped contacts makeengagement for re ucing the resistance through said inner pair ofcontacts, said inner pair of contacts being formed of -metal of higherconductivity than the metal forming the outer ring shaped contacts.

In testimony whereof I hereunto afl'ix my signature.

CHARLES THOMAS MASON.

